AMNIOTIC FLUID SPECTROPHOTOMETRY AND EARLY DELIVERY IN THE MANAGEMENT OF ERYTHROBLASTOSIS FETALIS

Abstract

Accuracy of prediction of intrauterine death in erythroblastosis fetalis, using history of disease and antibody titer alone, is limited (62% accuracy in a series of 121 perinatal deaths and babies who survived only because they were delivered early). Chief sources of error are in first sensitized pregnancies and in isoimmunized pregnancies where the mother has a bad history and a heterozygous husband. Spectrophotometric examination of amniotic fluid obtained transabdominally as early as 24 weeks' gestation has increased our accuracy of prediction of severity of disease to 96.8% in a series of 252 Rh negative isoimmunized pregnancies from whom 402 suitable fluids were obtained and examined. Only one of the eight inaccuracies was of such a degree that the infant's life was threatened. In 32 pregnancies with histories of severe disease on high titers and heterozygous husbands, accuracy of prediction of the Rh status of the fetus was 100 per cent. The procedure carries no risk to the mother, but if the placenta is traversed, her antibody titer may rise and the severity of the disease in the fetus may be increased. Liquor examination allows more accurate timing of induction in threatened intrauterine death and saves less severely affected babies from the hazards of prematurity. It has also proven of value in determining the fetus so severely affected that survival is only possible through intraperitoneal fetal transfusions.